Today, the interest in developing and improving alternative lighting devices has greatly increased due to the removal of incandescent light bulbs on the market. This has further lead to increased demands on reduced production costs and to increase the performance of the alternative lighting devices. For example, lighting devices with light emitting diodes have several advantages compared to other conventional lighting, including for example high energy efficiency, high light output and long service life. Therefore, light emitting diodes have also started to be incorporated into lighting devices, replacing the traditional fluorescent lamps and incandescent lamps commonly found in offices, and other general places.
However, the use of light emitting diodes in general lighting is commonly associated with problems relating to unsatisfactory illumination distribution, such as limited output distributions. A large number of light emitting diodes are generally a necessity for providing a lighting device with a desired light distribution transmitting light in a multitude of directions. However, with increasing number of light emitting diodes or light sources high costs inevitably follows as well as increasing the demand on available space for providing efficient placement for accommodating the increasing number of the light sources, leading to decreasing cost efficiency for the lighting device. Furthermore, increasing the number of lighting devices leads to more complicated and complex structures and, thus, places a higher demand on the production process.
A general problem for lighting devices having a substrate protruding from a lamp base is that a plurality of light sources needs to be arranged on the substrate to provide a desired light distribution. Furthermore, to provide more or less omnidirectional lighting both sides of the substrate needs to be arranged with a plurality of light sources leading to high production costs and inefficient production.
However, it would be advantageous to provide a lighting device with an improved illumination distribution through a simple and cost efficient production process.